Method op and apparatus eor producing ammonium suleate



H. A. CARPENTER.

METHOD OF-AND APPARATUS FOR PRODUCING AMMONIUM SULFATE.

APPLICATION FILED FEB. 15! I916.

1,322,?5Z Patented Nov. 25, 1919.

3 SHEETS-SHEET 1.

INVENTQR H. A. CARPENTER.

METHOD OF AND APPARATUS FOR PRODUCING AMMONIUM SULFATE.

APPLICATION FILED FEB. 15, 1916.

1,322,757 I Patented Nov. 25, 1919.

3 SHEETSSHEET Z.

mg. 2 I

WW I

H. A. CARPENTER. METHOD OF AND APPARATUS FOR PRODUCING IAMMONIIUMSULFATE.

APPLICATION FILED FEB. 15, 1916.

Lfi fifiih Patented Nov. 25, 1919.

3 SHEETS-SHEET 3.

INVENTOR the bath may TYMTED STATES @FFTQE.

HENRY A. CARPENTER, OF SEWICKLEY, PENNSYLVANIA, ASSIGN OR TORITER-CONLEY MANUFACTURING COMPANY, OF PITTSBURGH, PENNSYLVANIA, ACORPORATION OF NEW JERSEY.

METHOD OF AND APPARATUS FOR PRODUCING AMMQNIUM SULFATE.

Specification of Letters Patent.

Application filed February 15, 1916. Serial No. 78,444.

To all whom it may concern:

Be it known that T, HENRY A. CARPENTER, a citizen of the United States,and resident of Sewickley, in the county of Allegheny and State ofPennsylvania, have invented certain new and useful Improvements inMethods of and Apparatus for Producing I Ammonium Sulfate, is aspecification.

This invention relates to the production of sulfateof ammonia bysubjecting coal gas to an acid saturation bath, the desired reaction ofwhich the following resulting from contact of the ammonia ladengas withthe sulfuric acid content 'of the bath.

One object is to providea controlled or predetermined uniformtemperature condition within the saturator, and particularly at the gasoutlet thereof, whereby the reaction is caused. to proceed underconditions most favorable for the production of high-grade sulfate, andwhereby the temperature of the inlet as may be so regulated as to insurevaporization of water from the bath in desired .amount.

A further object is to utilize conditions inherent in the saturationbath for automatically controlling replenishment of the water and acidcontents thereof, avoiding either over or under supply and maintaining asaturation bath of uniform volume and acidity. .The level of the bath ispreferably utilized through the medium of a float for regulating thewater additions, and the acid replenishment is determined by thespecific gravity of the bath by means of a hydrometer.

Another object is to produce an acid-free sulfate, and this I accomplishby thoroughly washing the salt, waste" being revented by discharging theacid-carrying water into the saturator, and as the water whichreplenishes be used for this purpose, the desired conditions incident tothe bath and its maintenance are in no way disturbed. The washing ismade very effective by causing the Water to flow counter to and incontact with the sulfate as the latter is withdrawn from the saturator,whereby the sulfate is discharged free of acid.

Another object is to insure thorough and complete dissemination of theacid content throughout the saturation bath, the latter being usuallyabout'a 5 %'solution. The addition of a small amount of acid of greatconcentration to the relatively large volume of the bath rendersthorough mixing diliicult if not impossible if attempted in that zone orportion of the bath entered by the gas. To circumvent this unfavorablecondition I maintain the bath in two bodies, with means for maintainingconstant circulation between them. The reaction takes place in one ofthe bodies and the acid replenishment is accomplished in the other body,and by this means a thorough and uniform mixture is had, particularly inthat portion of the bath where the reaction takes place.

In Figures 1 and 2 of the accompanying drawings apparatus for practisingthe invention is illustrated, the showing in both views being largelydiagrammatic, Fig. 1 illustratipg the same primarily in side elevationwith t 1e while in Fig. 2 the electrical circuits and connections areshown, together with a vertical section of the auxiliary saturator bathchamber. Fig. 3 is a detail of the mechanisms actuated by the float andhydrometer for eflecting the opening and closing of the circuitscontrolled thereby. Fig. 4 is a View in vertical section of the mainsaturator chamber together with a form of conveyer for removing thesulfate therefrom, and Fig. 5 is a sectional plan of a portion of thechamber, taken on line 55 of Fig. 4. Fig. 6 is a view in verticalsection of part of the structure mounted on the saturation chamber forsupporting and operating the conveyor, the

parts being illustrated at right angles to that shown in Fig. 4. Fig. 7illustrates one of the conveyer buckets in detail.

Referring to the drawings, 2 designates the saturator, and 8 the pipefor admitting coal gas thereto, the gas passing into the uppercompartment 4 of the saturator at the eXterior of the dome 5. Space etisin free communication with the jacket-like space 6, the latter beingformed by the downward continuation 7 of dome 5 and the outer wall 8 ofchamber 2. Space 6 is in open communication beneath the level of thebath with the interior of the saturation chamber. From thechamber-encircling space tithe gas is conducted into the hollow radiallyarranged distributin the level of the bat various electric connectionsomitted,.

Patented Nov. 25, 19-19.

tive distribution throughout all portions of the gas-entering Zone ofthe bath. The pres sure of gas is sufficient to depress the liquid levelin space 6, so that the gas may freely enter distributers 9, as shown inFig. 4. Upon emerging from the bath the gas ascends into dome 5 fromwhich it passes through discharge pipe 11.

lt is desirable to regulate the temperature of the gas within thesaturation cham ber. One object of such regulation to maintain the gasat an eflicient absorbing temperature, whereby the Water content of thebath will be depleted in such amount that the Water required toreplenish the same will be sniiicient to thoroughly wash. the sulfate asit is withdrawn from the saturator, producing an acid-free salt. Anotherobject of such regulation is to maintain. the temperature as low as isconsistent with an efficient reaction, a better grade of sulfate beingthus produced than when the temperature is excessive. A function of thesaturator is availed of for accomplishing this automatic regulation, andin the preferred practice the temperature of the gas discharging fromthe saturator is thus utilized.

'In the embodiment of the tempe'ature regulation here shown, 15designates a gas heater of usual construction through which acirculation of heated waste gases may be maintained by blower 16. Thegas to be actuated by a thermostat 2% of suitable typeheated enters froma main 1? and discharges through pipe 18 into the saturator inlet 3.Extending around the heater from main 1.7 to inlet 3 is bypass l9, andcontrolling the flow to the heater and to the bypass is a damper 20which is adapted to be actuated by an electric motor 21, which is byprefer- 'ence connected to a three-phase circuit 22 by a reversingswitch 23 of familiar construction, and this switch is adapted to behaving its terminal 25 entered in the saturator gas outlet 11. By thismeans both heated and relatively cool gas is passed to the saturator,the proportion of each being determined by damper 20 which, in turn,

is controlled automatically by the temperature at the saturator outlet,the reversing switch operating to actuate the motor in direction toadmit more or less heated or cooled gas, or to remain inactive when theswitch is in neutral position, all as determined by the movementemanating from thermostat 24.

The invention embodies automatic regulation for controlling thereplenishment of the water and acid contents of the saturation bath, butbefore describing these features referent. will be made to thedisposition of the bath in two separate bodies between which constantcirculation of the liquid is maintained.

Upon referring to the drawings, it will portion of the bath that isrequired to be of maximum acidity, 2., the portion w th which the gas isin contact after discharg ing from battles 9. Also, with the circulation outlc leading from the upper portion of the saturation bath thereis practically no Withdrawal of sulfate into chamber 30. Circulation ismaintained by means of a pump 36 driven by motor 37 and to which pipe 32is connected, and by this means the contents of chambers 2 and 30 areconstantly mixing and interchanging.

The advantage of the foregoing arrangement results from the fact thatthe relatively small amount of acid of high concentration is supplied tochamber 30 and is thoroughly mixed with the saturation bath in saidchamber and before reaching chamber 2., \Vhereas, if the acid wereintroduced directly into chamber 2 there would be no opportunity forobtaining a thorough mixing and to that extent the operation of thesaturator would lack uniformity and its efficiency would becorrespondingly lessened.

Functions of the saturation bath are utilized for automaticallycontrolling the inflow of water and acid, whereby the volume and acidityof the bath are main tained substantially constant. The water supply maybe obtained from a main. i0

which is adapted to discharge into the con veyer tube 41 (presently todescribed) extending downwardly into =ti .t open to the lower portion or5-3 and and switch. By this means the flow of water through main 40 maybe accurately controlled, motor at?) being controlled by the switch toeither decrease or increase the flow or to maintain a predetermined con.stant flow, determined by the liquid level of chamber 30.

The supply of acid may be drawn from a suitable elevated container 50, avalve 51 controlling the flow therefrom into chamber A reversibleelectric motor 52 for actuating this valve is connected in circuit 22,the direction of themotor being controlled by a solenoid reversingswitch conventionally shown at 53. This switch is under the com rol ofhydrometer 5% located in chamber 30, the hydrometer stem 55 beingmovable through a vertical guide 56 carried by the float and at itsupper end pivotally connected to one end of lever 57. This lever ismounted between its ends on fulcrum e7, being thus fulcrumedcoincidentally with lever 526. the circuit extending to one side ofswitch is movably supported at 59 by lever 46, and said interruption isadapted to be closed by the bridging contact 60 carried by one leg oflever 57 when the hydrometer has risen sufficiently to effect suchoperation. A like interruption (51 in the branch of the circui extendingto the other portion of switch .33 is movably carried by the oppositeleg of lever t6, and is adapted to be closed by the bridging contact 62movably carried by the portion of lever 57 that is distant from contact(30. As variations in the liquid level have substantially the sameposition-changing elfect on the float and hydrometer, levers l6 and 57have substantially the same moven'ient on their common fulcrum 4:7 inresporse to such variations. This results in maintaining the circuitinterruptions 58 and ($1 in substantially the same relation to contacts0 and (32 irrespective of liquid level changes, and hence said parts arein proper relation for controlling the direction of motor 52 by movement[of the hydrometer relatively to the float, determined by the spe cificgravity of the bath. I

The quality of ammonium sulfate is frequently seriously impaired by thepresence of sulfuric acid which is of a viscous nature and adheres tothe salt in such manner that ts removal presents a difficult problem.Also the acid removed from the bath with the sulfate is an element ofwaste. The present invention provides for effectively washing thesulfate during its withdrawal from the saturator so that it isdischarged from the apparatus in a non-acid state The means here shownfor accomplishing this purpose consists of an endless conveyer chain (35within tube 41 and carrying perforated or open mesh buckets 66. Thisconveyer is mounted in tube 41 on the upper and lower sprocket wheels 67and 68, respectively, jUIH'LHlctl in the vertical parallel arms of asupporting frame. The upper end of this .l'rann comprises a spindle 70that is rotatablev in bearings 71 of frame 72, the latlcr mounted onsaturator 2, a motor 73 being eared to the spindle at 7 whereby thecndloss conveyor and its support are rotated about ,vertical axiswithout interfering An interruption 58 in the branch of thereof.

veyer support about its vertical axis operates to drive the uppersprocket, thereby keeping the conveyer in motion. Buckets 66 are thuscaused to fill with sulfate at the lower end of tube 41 and discharge atthe upper end of said tube.

The movement of the conveyer about a vertical axis combined with thevertical travel of the buckets results in so agitating sulfate at thelower end of tube tl as to maintain an ample supply Within-reach of thebuckets atall times. 7 9 projecting laterally from the lower extremityof frame 69, Figs. 4c and 5, sweep through the sulfate as the frame isrotated, thus still further agitating the same. At the upper end of theconveyer the inflowing fresh water is discharged from pipe 40 throughthe ring or manifold 48 so that the sulfate is thoroughly washed whilebeing. elevated through tube 41 and is freed of the acid adheringthereto, the water draining therefrom through the ascending perforatedbuckets.

It is characteristic of the cleansing operation that the sulfate andwater move or flow in opposite directions through a common path ofsubstantial length with the scrubbin action proceeding from end to endThe sulfate encounters progressively clearer or fresher water as itmoves toward the discharge end of the conveyer, whereby a most effectivewashing and rinsing action is had. \Vhile this contra-current washing ispreferably practised with the water which replenishes the bath, andwhile in such practice the temperature regulation of the saturatorissuch as to require an amount of inflowing water suflicient to thoroughlycleanse the sulfate, the invention is not restricted thereto.

I claim:

.1. In the production of sulfate of ammonia by treating coal gas in anacid saturation bath, the method herein described of freeing the sulfateof acid, consisting in sub- Plow-like arms jecting the sulfate to acleansing liquid, with sisting in introducing coal gas into an acidsaturation bath in condition to cause it to absorb water from the bath,replenishing the water content of the bath, and'"simultaneouslywithdrawing the ammonium sulfate in opposite direction to theentering'water and in contact therewith.

a. In the production of sulfate of am monia, the method hereindescribed, consisting in introducing coal gas into an acid saturationbath in condition to cause it to absorb water from the bath, elevatingand thereby withdrawing the ammonium sulfate from the bath, andreplenishing the water content of the bath by introducing waterthereinto in contra-current to the discharging sulfate and in contacttherewith.

5. In apparatus for producing sulfate of ammonia, a saturator containingan acid bath adapted to receive coal gas and form ammonium sulfate,means for withdrawing the sulfate, and-means for washing the sulfate asitis being withdrawn.

6. In apparatus for producing sulfate of ammonia, a saturator containingan acid J bath adapted to receive coal gas and form ammonium sulfate,and a source of water for replenishing the bath with the water movingoppositely to and in contact with the sulfate as the latter iswithdrawn.

I 7. In apparatus for producing sulfate of ammonia, a saturatorcontaining an acid bath adapted to receive coal gas and form ammoniumsulfate, a conveyer for removing the sulfate from the bath, and meansfor bodily shifting the conveyer relatively to the accumulation ofsulfate within the saturator for causing the conveyer to act ondifferent portions of such accumulation.

8. In apparatus for producing sulfate of ammonia, a saturator containingan acid bath adapted to receive coal gas and form ammonium sulfate, anendless vertically movable conveyer extending upwardly from the lowerportion of the saturator, a con "eyer support, and means'for moving thesupportabout avertical axis.

9. 1n apparatus for producing sulfate of ammonia, a saturator containingan acid bath adapted to receive coal gas and form ammonium sulfate, asupport extending upently of its sulfate elevating movement, and

means for driving the' conveyer and for s1-- multaneously moving itbodily.

11. In apparatus'for producing sulfate of ammonia, a saturatorcontaining an acid bath adapted to receive coalgas and form ammoniumsulfate, a tube extending upwardly through the saturator and open to thelower portion of the latter, the upper portion of the tube open at theexterior of the saturator for discharging sulfate, and a conveyeroperative within the tube for withdrawing sulfate from the saturator.

12. In apparatus for producing sulfate of ammonia, a saturatorcontaining an acid.

bath adapted to receive coal gasand forfn ammonium sulfate, a tubeextending upwardly through the saturator and open to :the lower portionof the latter, the upper portion of the tube open at the exterior of thesaturator for discharging sulfate, a conveyer support rotatable in thetube about a vertical axis, and a conveyer mounted on the support.

13. In apparatus for producing sulfate of ammonia, a saturatorcontaining anacidbath adapted to receive coalgas and form sulfate ofammonium,"a sulfate removing conveyer for withdrawing the sulfate fromthe bath, and a source of water, for replenishing the bath with suchWater flowing through the conveyer in contra-current to the dischargingsulfate.

In testimony whereof, I allix my signature in presence'of two witnesses.

HENRY a. onarnurnaf Witnesses:

LEWIS VINoEN'r, ADA M. STEELE.

